1. Field of the Invention
The present invention relates to an operating device including an operating member driven by a drive device provided with a drive source, a method of controlling the operating member, and a circuit-board working apparatus including the operating member and a control device for controlling the operating member.
2. Description of Related Art
An operating device may include an operating member driven by a drive device provided with a drive source. In this type of operating device, an operating speed of the operating member during an operation thereof from a first position to a second position is initially smoothly increased from zero, subsequently smoothly reduced, and finally zeroed. JP-2004-272749 A discloses an example of such type of operating device wherein the operating member is an arm of a robot. A positioning control device described in this publication includes a letter-S position command generating portion configured to generate letter-S position commands according to which an acceleration value and an acceleration time of the robot arm are equal to an absolute value of a deceleration value and a deceleration time of the robot arm. A motor provided to operate the robot arm is controlled by the letter-S command generating portion, to control the position of the free end of the robot.
There also known positioning control devices wherein the letter-S position command generating portion is configured to generate letter-S position commands according to which the absolute value of the deceleration value is smaller than the acceleration value while the deceleration period is longer than the acceleration period, as indicated in FIG. 10, to reduce an impact and vibrations of the operating member upon its stopping, or letter-S position commands according to which the acceleration value and the deceleration value change along two sides of a triangle, to reduce an impact and vibrations of the operating member during the acceleration and deceleration of the operating member. There are also known positioning control devices wherein the letter-S position command generating portion is configured to generate letter-S position commands according to which the absolute value of the deceleration value is smaller than the acceleration value while the deceleration period is longer than the acceleration period, and the acceleration value and the deceleration value change along two sides of a triangle, as indicated in FIG. 11, to effectively reduce the vibrations upon stopping of the operating member and to assure a high degree of positioning accuracy of the operating member.